DTI在脑膜瘤、胶质瘤及转移瘤患者诊断及手术指导中的应用研究

目的研究磁共振扩散张量成像(DTI)在脑膜瘤、胶质瘤及转移瘤患者诊断及手术指导中的应用价值。方法选择本院2018年2月至2020年3月收治的100例颅内幕上肿瘤患者作为试验组,其中脑膜瘤34例,胶质瘤38例,转移瘤28例,包含良性脑肿瘤34例与恶性脑肿瘤66例,另选同期本院收治的54例颅内幕上肿瘤患者作为对照组。试验组患者术前均接受核磁共振成像(MRI)平扫及增强扫描,DTI检查,术中联合神经系统导航技术切除肿瘤;对照组患者术前均进行常规MRI平扫和增强扫描,并接受传统颅内肿瘤切除术。对比各组表观弥散系数(ADC值)、rADC值、各向异性分数(FA值)、rFA值,观察对照组和试验组手术肿瘤切除率,术后致残率及术后新发运动功能障碍率。结果脑膜瘤组肿瘤实质区ADC值、rADC值、FA值、rFA值均高于胶质瘤组及转移瘤组(P<0.05),胶质瘤组ADC值、rADC值低于转移瘤组(P<0.05);胶质瘤组与转移瘤组FA值及rFA值比较无统计学差异(P>0.05)。良性肿瘤组ADC值、rADC值、FA值、rFA值高于恶性肿瘤组(P<0.05)。恶性肿瘤瘤周白质区rADC值高于对侧正常白质区(P<0.05),FA值、rFA值低于对侧正常白质区(P<0.05),恶性肿瘤瘤周白质区与对侧正常白质区ADC值比较无统计学差异(P>0.05)。试验组肿瘤切除率明显高于对照组(P<0.05),术后致残率明显低于对照组(P<0.05),两组术后新发运动功能障碍率比较无统计学差异(P>0.05)。结论DTI检查能够利于颅内肿瘤类别的鉴别诊断,且可反映颅内肿瘤和周围白质纤维束的关系,指导临床手术方案的制定。     

脑胶质瘤治疗及其动物模型的研究进展

脑胶质瘤是原发性中枢神经细胞肿瘤中最常见并且死亡率最高的肿瘤。尽管对其研究的重视程度日渐增加,胶质瘤依然是现今最难治疗的肿瘤。许多候选药物在临床前试验有较好效果的药物在临床试验后期失败,提示动物模型的改进的必要性。随着药理学,药剂学与分子生物学研究的进展,建立科学的、可重复性好的动物模型对于胶质瘤的发病机制,评价药物疗效与给药方式有非常重要的意义。本文将目前对胶质瘤的治疗方法与动物模型的研究进行综述。     

Hippocampal-sparing radiotherapy: The new standard of care for World Health Organization grade II and III gliomas?

The neurocognitive effects of cranial radiotherapy in patients with gliomas are well-recognised and may be related to the dose delivered to the hippocampi. Intensity modulated radiotherapy (IMRT) is a radiotherapy technique that can be used to selectively spare the hippocampi without compromising the dose delivered to the tumour. This study aimed to evaluate if hippocampal-sparing IMRT is achievable in patients with World Health Organization (WHO) grade II and III gliomas. A retrospective review of consecutive patients with WHO grade II and III gliomas treated with IMRT at our institution between January 2009 and August 2012 was performed. Hippocampal-sparing was defined as a mean dose to at least one hippocampus of less than 30 Gy. The dose delivered to the tumour was never compromised to achieve the hippocampal dose constraint. Logistic regression analyses were performed to identify predictive factors for achieving hippocampal-sparing treatment. Eighteen patients were identified and hippocampal-sparing was achieved in 14 (78%). The median dose prescribed was 59.4 Gy in 33 fractions and 11 patients had WHO grade III gliomas. The mean dose to the contralateral hippocampus was 24.9 Gy. Planning target volumes less than 420.5 cm³ were more likely to enable hippocampal-sparing treatment to be given (hazard ratio 1.7, p = 0.03) and there was a trend with oligodendrogliomas and anaplastic oligodendrogliomas. Hippocampal-sparing radiotherapy is feasible in patients with WHO grade II and III gliomas. Oncologic outcomes are yet to be assessed prospectively. The relationship between hippocampal dose and neurocognitive function in adults is currently under investigation.     

注射维生素C治疗脑胶质瘤的实验研究

目的探讨维生素C治疗脑胶质瘤的作用机制,为胶质瘤的临床治疗提供实验室依据。方法制作大鼠C6脑胶质瘤模型。荷瘤7d后将Wistar大鼠随机分为5组,每组10只,即对照组;维生素C低剂量组（2．0g／kg）;维生素C中剂量组（4．0g／kg）;维生素C高剂量组（8．0g／kg）;5-Fu组（20mg／kg）。于用药结束后次日处死各组小鼠,计算肿瘤体积和抑瘤率;流式细胞术检测各组肿瘤组织细胞凋亡率;免疫组化法检测各组肿瘤组织Ki-67蛋白表达情况。结果维生素C可抑制大鼠肿瘤生长,且呈剂量依赖性,实验组肿瘤体积与对照组相比有显著差异（P〈0.05）,维生素C高剂量组与5--Fu组肿瘤体积比较无统计学差异（P〉0.05）。维生素C可诱导大鼠肿瘤细胞凋亡,维生素C各组与对照组相比均有极显著性差异（P〈0.01）,维生素C高剂量组凋亡率高于5-Fu组（P〈0.05）。免疫组化法检测肿瘤组织细胞Ki-67蛋白表达中,维生素C各组与对照组相比均有极显著性差异（P〈0.01）,维生素C高剂量组与5-Fu组细胞凋亡率比较无统计学差异（P〉0.05）。结论维生素C在-定剂量范围内可抑制C6大鼠脑胶质瘤的生长,诱导肿瘤细胞发生凋亡是其机制之一;药理剂量的维生素C能降低C6大鼠脑胶质瘤细胞增殖活性,具有-定的抗肿瘤作用。     

Applications of positron emission tomography in neuro-oncology: A clinical approach

The field of neuro-oncology is concerned with some of the most challenging and difficult to treat conditions in medicine. Despite modern therapies patients diagnosed with primary brain tumours often have a poor prognosis. Imaging can play an important role in evaluating the disease status of such patients. In addition to the structural information derived from MRI and CT scans, positron emission tomography (PET) provides important quantitative metabolic assessment of brain tumours. This review describes the use of PET with radiolabelled glucose and amino acid analogues to aid in the diagnosis of tumours, differentiate between recurrent tumour and radiation necrosis and guide biopsy or treatment. [¹⁸F]Fluorodeoxyglucose (FDG) is the tracer that has been used most widely because it has a 2 h half life and can be transported to imaging centres remote from the cyclotron and radiochemistry facilities which synthesise the tracers. The high uptake of FDG in normal grey matter however limits its use in some low grade tumours which may not be visualised. [¹¹C] methionine (MET) is an amino acid tracer with low accumulation in normal brain which can detect low grade gliomas, but its short 20 min half life has limited its use to imaging sites with their own cyclotron. The emergence of new fluorinated amino acid tracers like [¹⁸F]Fluoroethyl-l-tyrosine (FET) will likely increase the availability and utility of PET for patients with primary brain tumours. PET can, further, characterise brain tumours by investigating other metabolic processes such as DNA synthesis or thymidine kinase activity, phospholipid membrane biosynthesis, hypoxia, receptor binding and oxygen metabolism and blood flow, which will be important in the future assessment of targeted therapy.     

The expression and significance of dishevelled in human glioma

Background

The proto-oncogene dishevelled (Dvl) is a critical component of the Wnt/β-catenin signaling pathway, and its elevated expression in various tumor types is associated with malignancy. However, a role for Dvl in glioma has not been explored.

Materials and methods

To determine whether Dvl expression is elevated in human glioma, we examined the protein levels in 67 human glioma samples and 3 normal brain specimens by Western blotting and immunohistochemistry. To investigate a possible association of Dvl with the malignant phenotype in glioma, the correlation of the Dvl immunoreactivity score (IRS) with β-catenin IRS, the tumor proliferation index (PI), and tumor invasion index (II) were determined for each sample.

Results

The Dvl IRS, β-catenin IRS, PI, and II increased significantly with the pathologic grade of glioma (P <0.001) with average scores of 3.46 ± 3.45, 3.92 ± 3.28, 30.93 ± 17.92, and 20.43 ± 11.79, respectively. Furthermore, the PI and II were significantly higher for the Dvl-positive group than the Dvl-negative group (P <0.001). Correlation analysis demonstrated that β-catenin IRS, PI, and II were positively correlated with Dvl IRS.

Conclusions

Dvl overexpression may contribute to the malignant proliferation and invasion of human glioma.     

胶质瘤患者肿瘤组织和血浆中MMP-9的表达及意义

目的探讨胶质瘤患者肿瘤组织和血浆中基质金属蛋白酶-9(MMP-9)的表达、两者之间的关系及意义。方法收集40例胶质瘤患者病理标本、患者术前血浆及临床资料,分成高度恶性组和低度恶性组。10例因重度颅脑损伤而行内减压手术切除的脑组织和患者术前血浆,作为对照组。运用免疫组织化学染色法对胶质瘤组织标本中MMP-9表达进行半定量分析。运用酶联免疫吸附测定法检测血浆中总MMP-9浓度。结果 MMP-9在正常脑组织中无表达,高度恶性组瘤组织中MMP-9的表达显著高于低度恶性组(P=0.027)和对照组(P=0.000)。各级别胶质瘤组MMP-9血浆浓度均显著高于对照组(P0.001)。瘤组织MMP-9强阳性表达组血浆MMP-9浓度显著高于阴性组(P=0.022)和弱阳性组(P=0.048),血浆MMP-9浓度与相应肿瘤组织MMP-9的表达水平呈正相关(rs=0.530,P=0.000)。结论瘤组织MMP-9表达与胶质瘤恶性程度呈正相关,其高表达可能与胶质瘤的侵袭转移有关;胶质瘤患者血浆MMP-9浓度一定程度上反映出瘤组织中MMP-9表达水平。     

受照脑胶质瘤细胞诱导神经干细胞旁效应

目的 探讨受照脑胶质瘤细胞U251是否可通过在未受照神经干细胞（NSCs）中产生旁效应从而影响神经干细胞的增殖、干性及分化等特性。方法 将细胞分为NSCs组、NSCs+U251组（与U251共培养的NSCs）和NSCs+受照U251组（与10 Gy X射线照射后的U251共培养的NSCs）。采用插入式小室共培养U251和NSCs。通过细胞计数、测量神经球直径等方法评估NSCs增殖、成球能力的变化;采用免疫荧光实验检测Nestin蛋白的表达评估NSCs干性维持能力的变化;检测Tuj1、GFAP蛋白的表达、测量分化后神经元细胞的树突数目、轴突长度以及胶质细胞突起终端数、突起长度等评估神经干细胞分化能力的变化情况。结果 NSCs+受照U251组的细胞数量明显低于NSCs+U251组（t=2.52,P<0.05）;NSCs+受照U251组的Nestin阳性率和成球能力明显低于NSCs+U251组（t=-3.50,P<0.05）;NSCs+受照U251组向神经元和胶质细胞（t=6.09,P<0.05）分化的比例和程度也明显低于NSCs+U251组。结论 受照胶质瘤细胞可通过电离辐射旁效应显著抑制未受照神经干细胞的增殖、干性和分化能力。